I was in a fooling around mood so I fitted the Jake brake switch and engine stop lever:
I also took a first pass at the gear shift lever. It was originally a bit too long and bent in the wrong direction:
Here's what it looks like after a little time with a saw and rosebud:
I will have to complete the fitting after I put the seat back into the cab.
I started patching the holes that I cut in the firewall. I've found that it takes me a week to repair an afternoon's worth of cutting. I've tacked in the sheet metal for the driver's side.
The throttle pedal will be about 1-1/4" closer to me thanks to the "shoulders" on the DD. I mocked the pedal up, it has full travel. The repair clears the engine so all is good.